<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>测试</title>

</head>
<style>

    div{
        width: 300px;
        height: 100px;
        background-color: aquamarine ;
        color: white;
        font-size: 50px;
        text-align: center;
        border-radius: 5px;
        /*使得box-shadow样式进行过度动画*/
        transition: box-shadow 1s ease 1s ;

    }
    div:hover{
        box-shadow: 10px 10px 5px #888888;
    }
</style>
<body>

    <div>测试</div>
</body>
</html>